dimanche 21 septembre 2014

Animals that don't Exist

The Usugiri Cicada

The usugiri cicada,
Tibicen giridesu, is a cicada
native to Japan, and not found anywhere else in the world. It follows
the same life cycle as its cousin, the annual cicada, Tibicen
linnei, emerging from the earth
in late spring, and mating during the summer, when the tell-tale
sound of cicadas can be heard all over Japan.
But, unlike its cousin, the usugiri does not live exclusively from
tree sap. Although the larvae, just like those of other cicadas, will
bury underground and feed on the roots of plants, the adults have a
quite different approach.

Cicada-hunting
has always been popular in japan, where kids (and even adults) will
follow the sound of cicadas to find them. The same is done by the
natural predators of cicadas, and the insect usually
stop as soon as they sense movement close by. Not so the usugiri
cicada.

Tibicen giridesu
emits two sounds, one of which is heard most at the beginning of
summer, and one which is mostly heard at the end of the season. The
first sound, similar to the one of the annual cicada, is a way to
attract mates, and is stopped as soon as potential predators get
near. The second one, however, is designed to attract those same
predators. Once they are close enough, the usugiri cicada will use
its modified wings to jump at its prey, and, thanks to its powerful
mandibles and its front claws evolved for digging, burrow into the
predator. Once inside, it will eat its fill, and, using the
nourishment thus gained, produce a large number of eggs. The eggs are
laid in the carcass of the would-be predators, and hatch quickly.
They then gorge themselves, before burrowing into the ground and
hibernating. The whole process takes between one or two days.

In
the Edo period (1603 – 1868) the usugiri cicada where though to be
one of the most dangerous creatures in Japan, and the Shogunate
invested much effort into their eradication. It is even believed that
one of the reasons for the seclusion of Japan during that time where
rumors suggesting the insects had been smuggled in by a foreign power
in an attempt to destabilize the regime. However, active hunting of
the cicadas soon stopped, since it only gave them more prey and made
their numbers flourish.

It
is still a mystery to this day how this behavior came to evolve,
since attempting to burrow into a predator without the specialized
morphological features seen today would result in death almost all
the time. Even though cicadas are naturally adapted for digging, it
would still be impossible for other cicadas to dig into a living
animal. As philosopher Oishii
Manju put it:

“It
is one thing to plow the earth. It is quite another to plow life.”